Teenagers who smoke e-cigarettes are poisoning their bodies with the same chemicals present in traditional tobacco cigarettes, according to research released this week.

E-cigarettes, or vape pens, combine flavored fluid and nicotine to deliver a less harsh form of smoking. Research published this week in the journal Pediatrics finds that teens who only smoke tobacco-based cigarettes such as Marlboro and Camel brands have the highest levels of cancer-causing chemicals present in their bodies. Those who only vape had higher levels of certain chemicals in their body than traditional smokers and nonsmokers, tied to the "flavoring" used in many vape products. The rising number of young Americans smoking e-cigarettes are at great risk for exposing themselves to these cancerous contaminants despite the products being marketed as healthier.

The chemicals found in the e-cigarette users’ bodies were not itemized on the ingredient list of the vape liquids. Instead, they are thrown under the umbrella of the term “flavorings,” the researchers warned. Both forms of cigarette use caused the presence of much higher levels of dangerous chemicals in the users’ bodies, including acrylonitrile, acrolein, propylene oxide, acrylamide and crotonaldehyde, the team reported.

Teens who used only e-cigarettes, especially particularly sweet or flavored juices, had much higher levels of chemicals than those who don’t use either tobacco product.

“Among our e-cigarette–only participants, the use of fruit-flavored products produced significantly higher levels of the metabolites of acrylonitrile,” the researchers wrote. “Acrylonitrile is a highly poisonous compound used widely in the manufacture of plastics, adhesives and synthetic rubber,” the National Center for Biotechnology Information says on its website. Additionally, the EPA listed acrolein as “toxic to humans following inhalation, oral or dermal exposure.

The study testing associations between e-cigarette use and more established smoking habits was conducted by University of California San Francisco researchers Benjamin Chaffee, Shannon Lea Watkins and Stanton Glantz, who concluded that “e-cigarettes do not divert from, and may encourage, cigarette smoking.”

The relatively small study tested 67 teenagers who reported vaping, compared to 16 teens who both vape and smoke traditional tobacco cigarettes. A third group of 20 teens who do not smoke was also involved.

Teens smoking e-cigarettes, or vaping, were found to have ingested far more cancer-causing chemicals than people who reported smoking traditional tobacco cigarettes. Getty Images

“The presence of harmful ingredients in e-cigarette vapor has been established‍; we can now say that these chemicals are found in the body of human adolescents who use these products,” the researchers concluded. “Unlike adults, particularly cigarette smokers, who commonly report a desire to quit smoking as a main motivator for e-cigarette use, youth are more likely to cite curiosity as a reason to try e-cigarettes.”

The study found that young people using e-cigarettes who had smoked at least one cigarette would likely become an establish smoker—one who smokes more than 100 cigarettes—within one year. Despite massive gains in cutting cigarette use among young adults over the past few decades, e-cigarette use was the most common tobacco product among U.S. middle- and high-schoolers between 2014 and 2016, according to the Centers for Disease Control and Prevention.

The study cautioned that e-cigarettes are often promoted as a safer, healthier alternative to traditional tobacco smoking. However, several public health groups, the CDC and the surgeon general’s office believe that vaping first gets teens addicted to nicotine, which ultimately leads them to regular cigarette use.

The latest CDC report found that e-cigarettes were the most commonly used form of tobacco smoked by the 20 percent of high school students who reported any use at all. In 2016, the CDC reported that 11 percent of U.S. high schoolers had vaped in the past 30 days.

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